The present venture relates to computer network communication, and in particular to combining a plurality of cluster devices to operate as a single device and increase bandwidth in a point-to-point protocol such as the Institute of Electrical and Electronics Engineers (IEEE) standard 802.3ad for multiple Ethernet links.
The 802.3ad standard issued by the IEEE specifies how to use multiple Ethernet links to make a logical point-to-point connection. This standard is published by the IEEE and is available from their headquarters, 345 East 47th Street New York, N.Y. 10017. The IEEE is a well known organization to those skilled in the art of computer network communication. The standards of the IEEE are readily available and understandable to those skilled in the art of computer network communication. The IEEE standard 802.3ad is hereby incorporated by reference, as well as any portions of the entire 802 standard that may be relevant to 802.3ad. It is that those skilled in the art will be able to build a device that can adhere to the IEEE 802.3ad standard and meet the PICS performance in section 43B.6 of the standard. The present invention also relates to other point-to-point protocols and is not limited to the IEEE 802.3ad standard.
The IEEE 802.3ad standard assumes that the points of the connection are single devices and defines an optional Link Aggregation sublayer for use with CSMA/CD (carrier sense multiple access/collision detection) MACs (Media Access Control). Link Aggregation allows one or more links to be aggregated together to form a Link Aggregation Group, such that a MAC Client can treat the Link Aggregation Group as if it were a single link. To this end, it specifies the establishment of DTE to DTE logical links, which consist of N parallel instances of an 802.3 link all of which are full duplex point-to-point links operating at the same data rate.
U.S. Pat. No. 6,195,351 filed Jan. 28, 1998 discloses a Logical Switch Set (LSS) comprising two or more switches that act as a single packet forwarding device with specific connection rules. The single packet forwarding device is a single logical unit. The LSS may be used as either a redundant switch set (RSS) or as a Load Sharing Switch Set (LSSS). The maximum throughput of the LSSS increases with each additional switch. A LSSS can only interconnect with the other devices via trunked links that contain at least one physical connection to each switch. The RSS may include a trunk link connection and a resilient link connection. U.S. Pat. No. 6,195,351 is hereby incorporated by reference.
U.S. Pat. No. 6,195,349 filed Jan. 28, 1998 discloses a packet based high speed mesh forming a trunk cluster. The trunk cluster is constructed with a set of loosely coupled switches, a configuration protocol, trunked network interfaces, and optionally a reachablilty protocol. The trunk cluster provides a Logical LAN service. Each switch in the trunk cluster provides a single xe2x80x9cshared LANxe2x80x9d by interconnecting two or more links. The edge devices attached to the links run a trunk configuration protocol. The attached edge devices view the trunked ports as if trunked ports are connected to a shared LAN with multiple other attached devices. U.S. Pat. No. 6,195,349 is hereby incorporated by reference.
U.S. Pat. No. 6,347,073 filed Apr. 29, 1998 discloses a plurality of independent control lines used by I/O modules to determine which switch of a redundant switch set is the active or primary switch. Each line is drive by a different source. Each of these control lines are driven by one of a plurality of judges and each judge can read the other control lines which they are not driving. All the I/O modules can only read the control lines. Each judge makes a decision as to which switch should be the primary switch. Each decision is conveyed using the control lines. The I/O modules use these control lines to direct a multiplexer of the respective outside node to connect to the primary switch. A majority rules algorithm is used to always obtain the correct result in the face of a single error. U.S. Pat. No. 6,347,073 filed Apr. 29, 1998 is hereby incorporated by reference
U.S. Pat. 6,058,116 filed Apr. 15, 1998 discloses an arrangement of trunk clusters and a method for interconnecting trunk clusters wherein the interconnection method has no single point of failure, the bandwidth between trunk clusters is not limited by the throughput of a single switch, and faults are contained within each trunk cluster. A trunked interconnection structure is provided between trunk clusters. Each switch of a trunk cluster has a logical port connected to a trunked port. The trunked port or trunk port provides a physical connection to each trunk switch of another trunk cluster. Each trunk switch of the another trunk cluster has a logical port connected to a trunked port which in turn has physical connections to each switch of the first trunk cluster. Trunked interconnections isolate faults to a single trunk cluster, there is no single point of failure and the total throughput is not limited to any single switches capacity. This always provides a single loop free path from one trunk cluster to the other or others. Multiple trunk clusters may be interconnected using point-to-point connections. A high throughput campus interconnect trunk cluster can be used to connect each building data center trunk cluster. U.S. Pat. No. 6,058,116 filed Apr. 15, 1998 is hereby incorporated by reference.
It is a primary object of the present invention to provide a plurality of network devices as representing a single point device of the point-to-point protocol, such as the IEEE 802.3ad standard. The present invention makes it possible to have one or both of the points of the IEEE 802.3ad standard be multiple devices. The multiple devices of the present invention are configured to behave as a single point in such a way that the multiple devices still adhere to the 802.3ad standard. Thus the multi device point can be seamlessly connected to a conventional single device that supports the 802.3ad specification.
The present invention accomplishes this by providing a system with at least one, and preferably at least two, end devices that operate according to the point-to-point protocol. The two end devices communicate with each other through a trunk cluster formed from a plurality of cluster devices. More than one of the cluster devices are in communication with more than one of the end stations, and the cluster devices identify connected end stations. The cluster devices share the identity of the connected end stations and commonly connected end stations. Each of the cluster devices has a synchronization means for configuring each the cluster device in communication with the commonly connected end stations to use a same logical identity for the point-to-point protocol.
The synchronization means of each cluster device exchanges individual synchronization state data with the synchronization means of the other cluster devices. Each synchronization means then configures the respective cluster device dependent on the exchanged synchronization state data and its own synchronization state data. If there are only two substantially similar cluster devices, both synchronization means can use the same algorithms to determine respective configurations. Since both synchronization means will apply the algorithms to the same data, the configurations will be identical and compatible.
For a trunk cluster with a large number of cluster devices, and/or significantly different cluster devices, each of the synchronization means can include algorithms and communicate with each other to operate one of the synchronization means as a master synchronization means (MSM). The master synchronization means determines cluster synchronization data needed for configuring and operating the individual cluster devices in order for the individual cluster devices to communicate with the end device according to the IEEE standard 802.3ad. The master synchronization means transfers the cluster synchronization data to the plurality of cluster devices in the trunk cluster. Each synchronization means configures a respective cluster device according to the cluster synchronization data.
The master synchronization means can be chosen based on the synchronization state data of the individual cluster devices, or the election of the master synchronization means can be predetermined, such as by a system operator. Likewise the cluster synchronization data can be determined from the individual synchronization data of the cluster devices, or the cluster synchronization data can be predetermined, such as by a system operator.
The cluster devices communicate with the end devices through communication links. The communication of the individual synchronization data and the cluster synchronization data is performed through an intra-cluster interconnect (ICI.). The intra-cluster interconnect can be formed from dedicated network links between the cluster devices, or the intra-cluster interconnect can be included in the communication carried by the communication links. In either embodiment, each device in the trunk cluster has a unique identification for the intra-cluster interconnect communication. The communication across the intra-cluster interconnect is based on the unique identification of the individual cluster devices. The design of the intra-cluster interconnect is well within the ability of those skilled in the art of computer network communication, and the exact design of the intra-cluster interconnect is not part of the scope of the present invention.
In a preferred embodiment, each of the cluster devices has means for operating according to be IEEE standard 802.3ad, and this means is configurable by the synchronization means of the present invention. The present invention is not limited to two single end devices communicating through a trunk cluster, but instead a plurality of trunk clusters could communicate with each other according to the 802.3ad standard, where each trunk cluster appears as a single point device according to the 802.3ad standard.
The present invention is an improvement over the 802.3ad standard, since additional bandwidth can be added to an end device by taking advantage of additional network devices. In the 802.3ad standard, additional bandwidth can only be added by adding additional communication links that directly connected two devices. If one of the devices has less ports than the other, bandwidth of the device having more ports is wasted with the IEEE standard 802.3ad. With the present invention a plurality of cluster devices having a small number of ports can be connected to a single 802.3ad device to take full advantage of all the ports of the single 802.3ad device. The present invention provides efficient configuration of a computer network which will increase the rate at which a computer network can transfer data, and/or reduce the equipment needed to insure an adequate data rate. The plurality of network devices representing a single 802.3ad device also increases reliability of a network by eliminating a single point of failure.
The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which preferred embodiments of the invention are illustrated.